Answer:
D
Step-by-step explanation:
We can assume that the rim of the canyon is 0. Sarah started 3 miles <u>below</u>, so -3, BUT distance can never be negative, so it's considered 3 miles. Then, she went 8 miles <u>above</u> zero. So the 3 miles she went <em>before</em> reaching the rim plus the 8 miles she went <em>after</em> reaching the rim equals 11 miles.
So now we know that Sarah is right, but how do we know which equation is correct? Well, if we look at option C:
When solving absolute value, we solve everything within the absolute value before applying the absolute value. This means that we add -3+8 first, which equals 5, and then apply absolute value, which still equals 5. This equation is not correct.
I hope this helps!